usb.h

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#ifndef __LINUX_USB_H
#define __LINUX_USB_H

#include <linux/mod_devicetable.h>
#include <linux/usb/ch9.h>

#define USB_MAJOR           180
#define USB_DEVICE_MAJOR        189


#ifdef __KERNEL__

#include <linux/errno.h>        /* for -ENODEV */
#include <linux/delay.h>    /* for mdelay() */
#include <linux/interrupt.h>    /* for in_interrupt() */
#include <linux/list.h>     /* for struct list_head */
#include <linux/kref.h>     /* for struct kref */
#include <linux/device.h>   /* for struct device */
#include <linux/fs.h>       /* for struct file_operations */
#include <linux/completion.h>   /* for struct completion */
#include <linux/sched.h>    /* for current && schedule_timeout */
#include <linux/mutex.h>    /* for struct mutex */
#include <linux/pm_runtime.h>   /* for runtime PM */

struct usb_device;
struct usb_driver;
struct wusb_dev;

/*-------------------------------------------------------------------------*/

/*
 * Host-side wrappers for standard USB descriptors ... these are parsed
 * from the data provided by devices.  Parsing turns them from a flat
 * sequence of descriptors into a hierarchy:
 *
 *  - devices have one (usually) or more configs;
 *  - configs have one (often) or more interfaces;
 *  - interfaces have one (usually) or more settings;
 *  - each interface setting has zero or (usually) more endpoints.
 *  - a SuperSpeed endpoint has a companion descriptor
 *
 * And there might be other descriptors mixed in with those.
 *
 * Devices may also have class-specific or vendor-specific descriptors.
 */

struct ep_device;

struct usb_host_endpoint {
    struct usb_endpoint_descriptor      desc;
    struct usb_ss_ep_comp_descriptor    ss_ep_comp;
    struct list_head        urb_list;
    void                *hcpriv;
    struct ep_device        *ep_dev;    /* For sysfs info */

    unsigned char *extra;   /* Extra descriptors */
    int extralen;
    int enabled;
};

/* host-side wrapper for one interface setting's parsed descriptors */
struct usb_host_interface {
    struct usb_interface_descriptor desc;

    int extralen;
    unsigned char *extra;   /* Extra descriptors */

    /* array of desc.bNumEndpoint endpoints associated with this
     * interface setting.  these will be in no particular order.
     */
    struct usb_host_endpoint *endpoint;

    char *string;       /* iInterface string, if present */
};

enum usb_interface_condition {
    USB_INTERFACE_UNBOUND = 0,
    USB_INTERFACE_BINDING,
    USB_INTERFACE_BOUND,
    USB_INTERFACE_UNBINDING,
};

struct usb_interface {
    /* array of alternate settings for this interface,
     * stored in no particular order */
    struct usb_host_interface *altsetting;

    struct usb_host_interface *cur_altsetting;  /* the currently
                     * active alternate setting */
    unsigned num_altsetting;    /* number of alternate settings */

    /* If there is an interface association descriptor then it will list
     * the associated interfaces */
    struct usb_interface_assoc_descriptor *intf_assoc;

    int minor;          /* minor number this interface is
                     * bound to */
    enum usb_interface_condition condition;     /* state of binding */
    unsigned sysfs_files_created:1; /* the sysfs attributes exist */
    unsigned ep_devs_created:1; /* endpoint "devices" exist */
    unsigned unregistering:1;   /* unregistration is in progress */
    unsigned needs_remote_wakeup:1; /* driver requires remote wakeup */
    unsigned needs_altsetting0:1;   /* switch to altsetting 0 is pending */
    unsigned needs_binding:1;   /* needs delayed unbind/rebind */
    unsigned reset_running:1;
    unsigned resetting_device:1;    /* true: bandwidth alloc after reset */

    struct device dev;      /* interface specific device info */
    struct device *usb_dev;
    atomic_t pm_usage_cnt;      /* usage counter for autosuspend */
    struct work_struct reset_ws;    /* for resets in atomic context */
};
#define to_usb_interface(d) container_of(d, struct usb_interface, dev)

static inline void *usb_get_intfdata(struct usb_interface *intf)
{
    return dev_get_drvdata(&intf->dev);
}

static inline void usb_set_intfdata(struct usb_interface *intf, void *data)
{
    dev_set_drvdata(&intf->dev, data);
}

struct usb_interface *usb_get_intf(struct usb_interface *intf);
void usb_put_intf(struct usb_interface *intf);

/* this maximum is arbitrary */
#define USB_MAXINTERFACES   32
#define USB_MAXIADS     (USB_MAXINTERFACES/2)

struct usb_interface_cache {
    unsigned num_altsetting;    /* number of alternate settings */
    struct kref ref;        /* reference counter */

    /* variable-length array of alternate settings for this interface,
     * stored in no particular order */
    struct usb_host_interface altsetting[0];
};
#define ref_to_usb_interface_cache(r) \
        container_of(r, struct usb_interface_cache, ref)
#define altsetting_to_usb_interface_cache(a) \
        container_of(a, struct usb_interface_cache, altsetting[0])

struct usb_host_config {
    struct usb_config_descriptor    desc;

    char *string;       /* iConfiguration string, if present */

    /* List of any Interface Association Descriptors in this
     * configuration. */
    struct usb_interface_assoc_descriptor *intf_assoc[USB_MAXIADS];

    /* the interfaces associated with this configuration,
     * stored in no particular order */
    struct usb_interface *interface[USB_MAXINTERFACES];

    /* Interface information available even when this is not the
     * active configuration */
    struct usb_interface_cache *intf_cache[USB_MAXINTERFACES];

    unsigned char *extra;   /* Extra descriptors */
    int extralen;
};

/* USB2.0 and USB3.0 device BOS descriptor set */
struct usb_host_bos {
    struct usb_bos_descriptor   *desc;

    /* wireless cap descriptor is handled by wusb */
    struct usb_ext_cap_descriptor   *ext_cap;
    struct usb_ss_cap_descriptor    *ss_cap;
    struct usb_ss_container_id_descriptor   *ss_id;
};

int __usb_get_extra_descriptor(char *buffer, unsigned size,
    unsigned char type, void **ptr);
#define usb_get_extra_descriptor(ifpoint, type, ptr) \
                __usb_get_extra_descriptor((ifpoint)->extra, \
                (ifpoint)->extralen, \
                type, (void **)ptr)

/* ----------------------------------------------------------------------- */

/* USB device number allocation bitmap */
struct usb_devmap {
    unsigned long devicemap[128 / (8*sizeof(unsigned long))];
};

/*
 * Allocated per bus (tree of devices) we have:
 */
struct usb_bus {
    struct device *controller;  /* host/master side hardware */
    int busnum;         /* Bus number (in order of reg) */
    const char *bus_name;       /* stable id (PCI slot_name etc) */
    u8 uses_dma;            /* Does the host controller use DMA? */
    u8 uses_pio_for_control;    /*
                     * Does the host controller use PIO
                     * for control transfers?
                     */
    u8 otg_port;            /* 0, or number of OTG/HNP port */
    unsigned is_b_host:1;       /* true during some HNP roleswitches */
    unsigned b_hnp_enable:1;    /* OTG: did A-Host enable HNP? */
    unsigned no_stop_on_short:1;    /*
                     * Quirk: some controllers don't stop
                     * the ep queue on a short transfer
                     * with the URB_SHORT_NOT_OK flag set.
                     */
    unsigned sg_tablesize;      /* 0 or largest number of sg list entries */

    int devnum_next;        /* Next open device number in
                     * round-robin allocation */

    struct usb_devmap devmap;   /* device address allocation map */
    struct usb_device *root_hub;    /* Root hub */
    struct usb_bus *hs_companion;   /* Companion EHCI bus, if any */
    struct list_head bus_list;  /* list of busses */

    int bandwidth_allocated;    /* on this bus: how much of the time
                     * reserved for periodic (intr/iso)
                     * requests is used, on average?
                     * Units: microseconds/frame.
                     * Limits: Full/low speed reserve 90%,
                     * while high speed reserves 80%.
                     */
    int bandwidth_int_reqs;     /* number of Interrupt requests */
    int bandwidth_isoc_reqs;    /* number of Isoc. requests */

#if defined(CONFIG_USB_MON) || defined(CONFIG_USB_MON_MODULE)
    struct mon_bus *mon_bus;    /* non-null when associated */
    int monitored;          /* non-zero when monitored */
#endif
};

/* ----------------------------------------------------------------------- */

/* This is arbitrary.
 * From USB 2.0 spec Table 11-13, offset 7, a hub can
 * have up to 255 ports. The most yet reported is 10.
 *
 * Current Wireless USB host hardware (Intel i1480 for example) allows
 * up to 22 devices to connect. Upcoming hardware might raise that
 * limit. Because the arrays need to add a bit for hub status data, we
 * do 31, so plus one evens out to four bytes.
 */
#define USB_MAXCHILDREN     (31)

struct usb_tt;

enum usb_device_removable {
    USB_DEVICE_REMOVABLE_UNKNOWN = 0,
    USB_DEVICE_REMOVABLE,
    USB_DEVICE_FIXED,
};

enum usb_port_connect_type {
    USB_PORT_CONNECT_TYPE_UNKNOWN = 0,
    USB_PORT_CONNECT_TYPE_HOT_PLUG,
    USB_PORT_CONNECT_TYPE_HARD_WIRED,
    USB_PORT_NOT_USED,
};

/*
 * USB 3.0 Link Power Management (LPM) parameters.
 *
 * PEL and SEL are USB 3.0 Link PM latencies for device-initiated LPM exit.
 * MEL is the USB 3.0 Link PM latency for host-initiated LPM exit.
 * All three are stored in nanoseconds.
 */
struct usb3_lpm_parameters {
    /*
     * Maximum exit latency (MEL) for the host to send a packet to the
     * device (either a Ping for isoc endpoints, or a data packet for
     * interrupt endpoints), the hubs to decode the packet, and for all hubs
     * in the path to transition the links to U0.
     */
    unsigned int mel;
    /*
     * Maximum exit latency for a device-initiated LPM transition to bring
     * all links into U0.  Abbreviated as "PEL" in section 9.4.12 of the USB
     * 3.0 spec, with no explanation of what "P" stands for.  "Path"?
     */
    unsigned int pel;

    /*
     * The System Exit Latency (SEL) includes PEL, and three other
     * latencies.  After a device initiates a U0 transition, it will take
     * some time from when the device sends the ERDY to when it will finally
     * receive the data packet.  Basically, SEL should be the worse-case
     * latency from when a device starts initiating a U0 transition to when
     * it will get data.
     */
    unsigned int sel;
    /*
     * The idle timeout value that is currently programmed into the parent
     * hub for this device.  When the timer counts to zero, the parent hub
     * will initiate an LPM transition to either U1 or U2.
     */
    int timeout;
};

struct usb_device {
    int     devnum;
    char        devpath[16];
    u32     route;
    enum usb_device_state   state;
    enum usb_device_speed   speed;

    struct usb_tt   *tt;
    int     ttport;

    unsigned int toggle[2];

    struct usb_device *parent;
    struct usb_bus *bus;
    struct usb_host_endpoint ep0;

    struct device dev;

    struct usb_device_descriptor descriptor;
    struct usb_host_bos *bos;
    struct usb_host_config *config;

    struct usb_host_config *actconfig;
    struct usb_host_endpoint *ep_in[16];
    struct usb_host_endpoint *ep_out[16];

    char **rawdescriptors;

    unsigned short bus_mA;
    u8 portnum;
    u8 level;

    unsigned can_submit:1;
    unsigned persist_enabled:1;
    unsigned have_langid:1;
    unsigned authorized:1;
    unsigned authenticated:1;
    unsigned wusb:1;
    unsigned lpm_capable:1;
    unsigned usb2_hw_lpm_capable:1;
    unsigned usb2_hw_lpm_enabled:1;
    unsigned usb3_lpm_enabled:1;
    int string_langid;

    /* static strings from the device */
    char *product;
    char *manufacturer;
    char *serial;

    struct list_head filelist;

    int maxchild;

    u32 quirks;
    atomic_t urbnum;

    unsigned long active_duration;

#ifdef CONFIG_PM
    unsigned long connect_time;

    unsigned do_remote_wakeup:1;
    unsigned reset_resume:1;
#endif
    struct wusb_dev *wusb_dev;
    int slot_id;
    enum usb_device_removable removable;
    struct usb3_lpm_parameters u1_params;
    struct usb3_lpm_parameters u2_params;
    unsigned lpm_disable_count;
};
#define to_usb_device(d) container_of(d, struct usb_device, dev)

static inline struct usb_device *interface_to_usbdev(struct usb_interface *intf)
{
    return to_usb_device(intf->dev.parent);
}

extern struct usb_device *usb_get_dev(struct usb_device *dev);
extern void usb_put_dev(struct usb_device *dev);
extern struct usb_device *usb_hub_find_child(struct usb_device *hdev,
    int port1);

#define usb_hub_for_each_child(hdev, port1, child) \
    for (port1 = 1, child = usb_hub_find_child(hdev, port1); \
        port1 <= hdev->maxchild; \
        child = usb_hub_find_child(hdev, ++port1))

/* USB device locking */
#define usb_lock_device(udev)       device_lock(&(udev)->dev)
#define usb_unlock_device(udev)     device_unlock(&(udev)->dev)
#define usb_trylock_device(udev)    device_trylock(&(udev)->dev)
extern int usb_lock_device_for_reset(struct usb_device *udev,
                     const struct usb_interface *iface);

/* USB port reset for device reinitialization */
extern int usb_reset_device(struct usb_device *dev);
extern void usb_queue_reset_device(struct usb_interface *dev);

#ifdef CONFIG_ACPI
extern int usb_acpi_set_power_state(struct usb_device *hdev, int index,
    bool enable);
extern bool usb_acpi_power_manageable(struct usb_device *hdev, int index);
#else
static inline int usb_acpi_set_power_state(struct usb_device *hdev, int index,
    bool enable) { return 0; }
static inline bool usb_acpi_power_manageable(struct usb_device *hdev, int index)
    { return true; }
#endif

/* USB autosuspend and autoresume */
#ifdef CONFIG_USB_SUSPEND
extern void usb_enable_autosuspend(struct usb_device *udev);
extern void usb_disable_autosuspend(struct usb_device *udev);

extern int usb_autopm_get_interface(struct usb_interface *intf);
extern void usb_autopm_put_interface(struct usb_interface *intf);
extern int usb_autopm_get_interface_async(struct usb_interface *intf);
extern void usb_autopm_put_interface_async(struct usb_interface *intf);
extern void usb_autopm_get_interface_no_resume(struct usb_interface *intf);
extern void usb_autopm_put_interface_no_suspend(struct usb_interface *intf);

static inline void usb_mark_last_busy(struct usb_device *udev)
{
    pm_runtime_mark_last_busy(&udev->dev);
}

#else

static inline int usb_enable_autosuspend(struct usb_device *udev)
{ return 0; }
static inline int usb_disable_autosuspend(struct usb_device *udev)
{ return 0; }

static inline int usb_autopm_get_interface(struct usb_interface *intf)
{ return 0; }
static inline int usb_autopm_get_interface_async(struct usb_interface *intf)
{ return 0; }

static inline void usb_autopm_put_interface(struct usb_interface *intf)
{ }
static inline void usb_autopm_put_interface_async(struct usb_interface *intf)
{ }
static inline void usb_autopm_get_interface_no_resume(
        struct usb_interface *intf)
{ }
static inline void usb_autopm_put_interface_no_suspend(
        struct usb_interface *intf)
{ }
static inline void usb_mark_last_busy(struct usb_device *udev)
{ }
#endif

extern int usb_disable_lpm(struct usb_device *udev);
extern void usb_enable_lpm(struct usb_device *udev);
/* Same as above, but these functions lock/unlock the bandwidth_mutex. */
extern int usb_unlocked_disable_lpm(struct usb_device *udev);
extern void usb_unlocked_enable_lpm(struct usb_device *udev);

extern int usb_disable_ltm(struct usb_device *udev);
extern void usb_enable_ltm(struct usb_device *udev);

static inline bool usb_device_supports_ltm(struct usb_device *udev)
{
    if (udev->speed != USB_SPEED_SUPER || !udev->bos || !udev->bos->ss_cap)
        return false;
    return udev->bos->ss_cap->bmAttributes & USB_LTM_SUPPORT;
}


/*-------------------------------------------------------------------------*/

/* for drivers using iso endpoints */
extern int usb_get_current_frame_number(struct usb_device *usb_dev);

/* Sets up a group of bulk endpoints to support multiple stream IDs. */
extern int usb_alloc_streams(struct usb_interface *interface,
        struct usb_host_endpoint **eps, unsigned int num_eps,
        unsigned int num_streams, gfp_t mem_flags);

/* Reverts a group of bulk endpoints back to not using stream IDs. */
extern void usb_free_streams(struct usb_interface *interface,
        struct usb_host_endpoint **eps, unsigned int num_eps,
        gfp_t mem_flags);

/* used these for multi-interface device registration */
extern int usb_driver_claim_interface(struct usb_driver *driver,
            struct usb_interface *iface, void *priv);

static inline int usb_interface_claimed(struct usb_interface *iface)
{
    return (iface->dev.driver != NULL);
}

extern void usb_driver_release_interface(struct usb_driver *driver,
            struct usb_interface *iface);
const struct usb_device_id *usb_match_id(struct usb_interface *interface,
                     const struct usb_device_id *id);
extern int usb_match_one_id(struct usb_interface *interface,
                const struct usb_device_id *id);

extern struct usb_interface *usb_find_interface(struct usb_driver *drv,
        int minor);
extern struct usb_interface *usb_ifnum_to_if(const struct usb_device *dev,
        unsigned ifnum);
extern struct usb_host_interface *usb_altnum_to_altsetting(
        const struct usb_interface *intf, unsigned int altnum);
extern struct usb_host_interface *usb_find_alt_setting(
        struct usb_host_config *config,
        unsigned int iface_num,
        unsigned int alt_num);


static inline int usb_make_path(struct usb_device *dev, char *buf, size_t size)
{
    int actual;
    actual = snprintf(buf, size, "usb-%s-%s", dev->bus->bus_name,
              dev->devpath);
    return (actual >= (int)size) ? -1 : actual;
}

/*-------------------------------------------------------------------------*/

#define USB_DEVICE_ID_MATCH_DEVICE \
        (USB_DEVICE_ID_MATCH_VENDOR | USB_DEVICE_ID_MATCH_PRODUCT)
#define USB_DEVICE_ID_MATCH_DEV_RANGE \
        (USB_DEVICE_ID_MATCH_DEV_LO | USB_DEVICE_ID_MATCH_DEV_HI)
#define USB_DEVICE_ID_MATCH_DEVICE_AND_VERSION \
        (USB_DEVICE_ID_MATCH_DEVICE | USB_DEVICE_ID_MATCH_DEV_RANGE)
#define USB_DEVICE_ID_MATCH_DEV_INFO \
        (USB_DEVICE_ID_MATCH_DEV_CLASS | \
        USB_DEVICE_ID_MATCH_DEV_SUBCLASS | \
        USB_DEVICE_ID_MATCH_DEV_PROTOCOL)
#define USB_DEVICE_ID_MATCH_INT_INFO \
        (USB_DEVICE_ID_MATCH_INT_CLASS | \
        USB_DEVICE_ID_MATCH_INT_SUBCLASS | \
        USB_DEVICE_ID_MATCH_INT_PROTOCOL)

#define USB_DEVICE(vend, prod) \
    .match_flags = USB_DEVICE_ID_MATCH_DEVICE, \
    .idVendor = (vend), \
    .idProduct = (prod)

#define USB_DEVICE_VER(vend, prod, lo, hi) \
    .match_flags = USB_DEVICE_ID_MATCH_DEVICE_AND_VERSION, \
    .idVendor = (vend), \
    .idProduct = (prod), \
    .bcdDevice_lo = (lo), \
    .bcdDevice_hi = (hi)

#define USB_DEVICE_INTERFACE_PROTOCOL(vend, prod, pr) \
    .match_flags = USB_DEVICE_ID_MATCH_DEVICE | \
               USB_DEVICE_ID_MATCH_INT_PROTOCOL, \
    .idVendor = (vend), \
    .idProduct = (prod), \
    .bInterfaceProtocol = (pr)

#define USB_DEVICE_INTERFACE_NUMBER(vend, prod, num) \
    .match_flags = USB_DEVICE_ID_MATCH_DEVICE | \
               USB_DEVICE_ID_MATCH_INT_NUMBER, \
    .idVendor = (vend), \
    .idProduct = (prod), \
    .bInterfaceNumber = (num)

#define USB_DEVICE_INFO(cl, sc, pr) \
    .match_flags = USB_DEVICE_ID_MATCH_DEV_INFO, \
    .bDeviceClass = (cl), \
    .bDeviceSubClass = (sc), \
    .bDeviceProtocol = (pr)

#define USB_INTERFACE_INFO(cl, sc, pr) \
    .match_flags = USB_DEVICE_ID_MATCH_INT_INFO, \
    .bInterfaceClass = (cl), \
    .bInterfaceSubClass = (sc), \
    .bInterfaceProtocol = (pr)

#define USB_DEVICE_AND_INTERFACE_INFO(vend, prod, cl, sc, pr) \
    .match_flags = USB_DEVICE_ID_MATCH_INT_INFO \
        | USB_DEVICE_ID_MATCH_DEVICE, \
    .idVendor = (vend), \
    .idProduct = (prod), \
    .bInterfaceClass = (cl), \
    .bInterfaceSubClass = (sc), \
    .bInterfaceProtocol = (pr)

#define USB_VENDOR_AND_INTERFACE_INFO(vend, cl, sc, pr) \
    .match_flags = USB_DEVICE_ID_MATCH_INT_INFO \
        | USB_DEVICE_ID_MATCH_VENDOR, \
    .idVendor = (vend), \
    .bInterfaceClass = (cl), \
    .bInterfaceSubClass = (sc), \
    .bInterfaceProtocol = (pr)

/* ----------------------------------------------------------------------- */

/* Stuff for dynamic usb ids */
struct usb_dynids {
    spinlock_t lock;
    struct list_head list;
};

struct usb_dynid {
    struct list_head node;
    struct usb_device_id id;
};

extern ssize_t usb_store_new_id(struct usb_dynids *dynids,
                struct device_driver *driver,
                const char *buf, size_t count);

extern ssize_t usb_show_dynids(struct usb_dynids *dynids, char *buf);

struct usbdrv_wrap {
    struct device_driver driver;
    int for_devices;
};

struct usb_driver {
    const char *name;

    int (*probe) (struct usb_interface *intf,
              const struct usb_device_id *id);

    void (*disconnect) (struct usb_interface *intf);

    int (*unlocked_ioctl) (struct usb_interface *intf, unsigned int code,
            void *buf);

    int (*suspend) (struct usb_interface *intf, pm_message_t message);
    int (*resume) (struct usb_interface *intf);
    int (*reset_resume)(struct usb_interface *intf);

    int (*pre_reset)(struct usb_interface *intf);
    int (*post_reset)(struct usb_interface *intf);

    const struct usb_device_id *id_table;

    struct usb_dynids dynids;
    struct usbdrv_wrap drvwrap;
    unsigned int no_dynamic_id:1;
    unsigned int supports_autosuspend:1;
    unsigned int disable_hub_initiated_lpm:1;
    unsigned int soft_unbind:1;
};
#define to_usb_driver(d) container_of(d, struct usb_driver, drvwrap.driver)

struct usb_device_driver {
    const char *name;

    int (*probe) (struct usb_device *udev);
    void (*disconnect) (struct usb_device *udev);

    int (*suspend) (struct usb_device *udev, pm_message_t message);
    int (*resume) (struct usb_device *udev, pm_message_t message);
    struct usbdrv_wrap drvwrap;
    unsigned int supports_autosuspend:1;
};
#define to_usb_device_driver(d) container_of(d, struct usb_device_driver, \
        drvwrap.driver)

extern struct bus_type usb_bus_type;

struct usb_class_driver {
    char *name;
    char *(*devnode)(struct device *dev, umode_t *mode);
    const struct file_operations *fops;
    int minor_base;
};

/*
 * use these in module_init()/module_exit()
 * and don't forget MODULE_DEVICE_TABLE(usb, ...)
 */
extern int usb_register_driver(struct usb_driver *, struct module *,
                   const char *);

/* use a define to avoid include chaining to get THIS_MODULE & friends */
#define usb_register(driver) \
    usb_register_driver(driver, THIS_MODULE, KBUILD_MODNAME)

extern void usb_deregister(struct usb_driver *);

#define module_usb_driver(__usb_driver) \
    module_driver(__usb_driver, usb_register, \
               usb_deregister)

extern int usb_register_device_driver(struct usb_device_driver *,
            struct module *);
extern void usb_deregister_device_driver(struct usb_device_driver *);

extern int usb_register_dev(struct usb_interface *intf,
                struct usb_class_driver *class_driver);
extern void usb_deregister_dev(struct usb_interface *intf,
                   struct usb_class_driver *class_driver);

extern int usb_disabled(void);

/* ----------------------------------------------------------------------- */

/*
 * URB support, for asynchronous request completions
 */

/*
 * urb->transfer_flags:
 *
 * Note: URB_DIR_IN/OUT is automatically set in usb_submit_urb().
 */
#define URB_SHORT_NOT_OK    0x0001  /* report short reads as errors */
#define URB_ISO_ASAP        0x0002  /* iso-only, urb->start_frame
                     * ignored */
#define URB_NO_TRANSFER_DMA_MAP 0x0004  /* urb->transfer_dma valid on submit */
#define URB_NO_FSBR     0x0020  /* UHCI-specific */
#define URB_ZERO_PACKET     0x0040  /* Finish bulk OUT with short packet */
#define URB_NO_INTERRUPT    0x0080  /* HINT: no non-error interrupt
                     * needed */
#define URB_FREE_BUFFER     0x0100  /* Free transfer buffer with the URB */

/* The following flags are used internally by usbcore and HCDs */
#define URB_DIR_IN      0x0200  /* Transfer from device to host */
#define URB_DIR_OUT     0
#define URB_DIR_MASK        URB_DIR_IN

#define URB_DMA_MAP_SINGLE  0x00010000  /* Non-scatter-gather mapping */
#define URB_DMA_MAP_PAGE    0x00020000  /* HCD-unsupported S-G */
#define URB_DMA_MAP_SG      0x00040000  /* HCD-supported S-G */
#define URB_MAP_LOCAL       0x00080000  /* HCD-local-memory mapping */
#define URB_SETUP_MAP_SINGLE    0x00100000  /* Setup packet DMA mapped */
#define URB_SETUP_MAP_LOCAL 0x00200000  /* HCD-local setup packet */
#define URB_DMA_SG_COMBINED 0x00400000  /* S-G entries were combined */
#define URB_ALIGNED_TEMP_BUFFER 0x00800000  /* Temp buffer was alloc'd */

struct usb_iso_packet_descriptor {
    unsigned int offset;
    unsigned int length;        /* expected length */
    unsigned int actual_length;
    int status;
};

struct urb;

struct usb_anchor {
    struct list_head urb_list;
    wait_queue_head_t wait;
    spinlock_t lock;
    unsigned int poisoned:1;
};

static inline void init_usb_anchor(struct usb_anchor *anchor)
{
    INIT_LIST_HEAD(&anchor->urb_list);
    init_waitqueue_head(&anchor->wait);
    spin_lock_init(&anchor->lock);
}

typedef void (*usb_complete_t)(struct urb *);

struct urb {
    /* private: usb core and host controller only fields in the urb */
    struct kref kref;       /* reference count of the URB */
    void *hcpriv;           /* private data for host controller */
    atomic_t use_count;     /* concurrent submissions counter */
    atomic_t reject;        /* submissions will fail */
    int unlinked;           /* unlink error code */

    /* public: documented fields in the urb that can be used by drivers */
    struct list_head urb_list;  /* list head for use by the urb's
                     * current owner */
    struct list_head anchor_list;   /* the URB may be anchored */
    struct usb_anchor *anchor;
    struct usb_device *dev;     /* (in) pointer to associated device */
    struct usb_host_endpoint *ep;   /* (internal) pointer to endpoint */
    unsigned int pipe;      /* (in) pipe information */
    unsigned int stream_id;     /* (in) stream ID */
    int status;         /* (return) non-ISO status */
    unsigned int transfer_flags;    /* (in) URB_SHORT_NOT_OK | ...*/
    void *transfer_buffer;      /* (in) associated data buffer */
    dma_addr_t transfer_dma;    /* (in) dma addr for transfer_buffer */
    struct scatterlist *sg;     /* (in) scatter gather buffer list */
    int num_mapped_sgs;     /* (internal) mapped sg entries */
    int num_sgs;            /* (in) number of entries in the sg list */
    u32 transfer_buffer_length; /* (in) data buffer length */
    u32 actual_length;      /* (return) actual transfer length */
    unsigned char *setup_packet;    /* (in) setup packet (control only) */
    dma_addr_t setup_dma;       /* (in) dma addr for setup_packet */
    int start_frame;        /* (modify) start frame (ISO) */
    int number_of_packets;      /* (in) number of ISO packets */
    int interval;           /* (modify) transfer interval
                     * (INT/ISO) */
    int error_count;        /* (return) number of ISO errors */
    void *context;          /* (in) context for completion */
    usb_complete_t complete;    /* (in) completion routine */
    struct usb_iso_packet_descriptor iso_frame_desc[0];
                    /* (in) ISO ONLY */
};

/* ----------------------------------------------------------------------- */

static inline void usb_fill_control_urb(struct urb *urb,
                    struct usb_device *dev,
                    unsigned int pipe,
                    unsigned char *setup_packet,
                    void *transfer_buffer,
                    int buffer_length,
                    usb_complete_t complete_fn,
                    void *context)
{
    urb->dev = dev;
    urb->pipe = pipe;
    urb->setup_packet = setup_packet;
    urb->transfer_buffer = transfer_buffer;
    urb->transfer_buffer_length = buffer_length;
    urb->complete = complete_fn;
    urb->context = context;
}

static inline void usb_fill_bulk_urb(struct urb *urb,
                     struct usb_device *dev,
                     unsigned int pipe,
                     void *transfer_buffer,
                     int buffer_length,
                     usb_complete_t complete_fn,
                     void *context)
{
    urb->dev = dev;
    urb->pipe = pipe;
    urb->transfer_buffer = transfer_buffer;
    urb->transfer_buffer_length = buffer_length;
    urb->complete = complete_fn;
    urb->context = context;
}

static inline void usb_fill_int_urb(struct urb *urb,
                    struct usb_device *dev,
                    unsigned int pipe,
                    void *transfer_buffer,
                    int buffer_length,
                    usb_complete_t complete_fn,
                    void *context,
                    int interval)
{
    urb->dev = dev;
    urb->pipe = pipe;
    urb->transfer_buffer = transfer_buffer;
    urb->transfer_buffer_length = buffer_length;
    urb->complete = complete_fn;
    urb->context = context;
    if (dev->speed == USB_SPEED_HIGH || dev->speed == USB_SPEED_SUPER)
        urb->interval = 1 << (interval - 1);
    else
        urb->interval = interval;
    urb->start_frame = -1;
}

extern void usb_init_urb(struct urb *urb);
extern struct urb *usb_alloc_urb(int iso_packets, gfp_t mem_flags);
extern void usb_free_urb(struct urb *urb);
#define usb_put_urb usb_free_urb
extern struct urb *usb_get_urb(struct urb *urb);
extern int usb_submit_urb(struct urb *urb, gfp_t mem_flags);
extern int usb_unlink_urb(struct urb *urb);
extern void usb_kill_urb(struct urb *urb);
extern void usb_poison_urb(struct urb *urb);
extern void usb_unpoison_urb(struct urb *urb);
extern void usb_block_urb(struct urb *urb);
extern void usb_kill_anchored_urbs(struct usb_anchor *anchor);
extern void usb_poison_anchored_urbs(struct usb_anchor *anchor);
extern void usb_unpoison_anchored_urbs(struct usb_anchor *anchor);
extern void usb_unlink_anchored_urbs(struct usb_anchor *anchor);
extern void usb_anchor_urb(struct urb *urb, struct usb_anchor *anchor);
extern void usb_unanchor_urb(struct urb *urb);
extern int usb_wait_anchor_empty_timeout(struct usb_anchor *anchor,
                     unsigned int timeout);
extern struct urb *usb_get_from_anchor(struct usb_anchor *anchor);
extern void usb_scuttle_anchored_urbs(struct usb_anchor *anchor);
extern int usb_anchor_empty(struct usb_anchor *anchor);

#define usb_unblock_urb usb_unpoison_urb

static inline int usb_urb_dir_in(struct urb *urb)
{
    return (urb->transfer_flags & URB_DIR_MASK) == URB_DIR_IN;
}

static inline int usb_urb_dir_out(struct urb *urb)
{
    return (urb->transfer_flags & URB_DIR_MASK) == URB_DIR_OUT;
}

void *usb_alloc_coherent(struct usb_device *dev, size_t size,
    gfp_t mem_flags, dma_addr_t *dma);
void usb_free_coherent(struct usb_device *dev, size_t size,
    void *addr, dma_addr_t dma);

#if 0
struct urb *usb_buffer_map(struct urb *urb);
void usb_buffer_dmasync(struct urb *urb);
void usb_buffer_unmap(struct urb *urb);
#endif

struct scatterlist;
int usb_buffer_map_sg(const struct usb_device *dev, int is_in,
              struct scatterlist *sg, int nents);
#if 0
void usb_buffer_dmasync_sg(const struct usb_device *dev, int is_in,
               struct scatterlist *sg, int n_hw_ents);
#endif
void usb_buffer_unmap_sg(const struct usb_device *dev, int is_in,
             struct scatterlist *sg, int n_hw_ents);

/*-------------------------------------------------------------------*
 *                         SYNCHRONOUS CALL SUPPORT                  *
 *-------------------------------------------------------------------*/

extern int usb_control_msg(struct usb_device *dev, unsigned int pipe,
    __u8 request, __u8 requesttype, __u16 value, __u16 index,
    void *data, __u16 size, int timeout);
extern int usb_interrupt_msg(struct usb_device *usb_dev, unsigned int pipe,
    void *data, int len, int *actual_length, int timeout);
extern int usb_bulk_msg(struct usb_device *usb_dev, unsigned int pipe,
    void *data, int len, int *actual_length,
    int timeout);

/* wrappers around usb_control_msg() for the most common standard requests */
extern int usb_get_descriptor(struct usb_device *dev, unsigned char desctype,
    unsigned char descindex, void *buf, int size);
extern int usb_get_status(struct usb_device *dev,
    int type, int target, void *data);
extern int usb_string(struct usb_device *dev, int index,
    char *buf, size_t size);

/* wrappers that also update important state inside usbcore */
extern int usb_clear_halt(struct usb_device *dev, int pipe);
extern int usb_reset_configuration(struct usb_device *dev);
extern int usb_set_interface(struct usb_device *dev, int ifnum, int alternate);
extern void usb_reset_endpoint(struct usb_device *dev, unsigned int epaddr);

/* this request isn't really synchronous, but it belongs with the others */
extern int usb_driver_set_configuration(struct usb_device *udev, int config);

/*
 * timeouts, in milliseconds, used for sending/receiving control messages
 * they typically complete within a few frames (msec) after they're issued
 * USB identifies 5 second timeouts, maybe more in a few cases, and a few
 * slow devices (like some MGE Ellipse UPSes) actually push that limit.
 */
#define USB_CTRL_GET_TIMEOUT    5000
#define USB_CTRL_SET_TIMEOUT    5000


struct usb_sg_request {
    int         status;
    size_t          bytes;

    /* private:
     * members below are private to usbcore,
     * and are not provided for driver access!
     */
    spinlock_t      lock;

    struct usb_device   *dev;
    int         pipe;

    int         entries;
    struct urb      **urbs;

    int         count;
    struct completion   complete;
};

int usb_sg_init(
    struct usb_sg_request   *io,
    struct usb_device   *dev,
    unsigned        pipe,
    unsigned        period,
    struct scatterlist  *sg,
    int         nents,
    size_t          length,
    gfp_t           mem_flags
);
void usb_sg_cancel(struct usb_sg_request *io);
void usb_sg_wait(struct usb_sg_request *io);


/* ----------------------------------------------------------------------- */

/*
 * For various legacy reasons, Linux has a small cookie that's paired with
 * a struct usb_device to identify an endpoint queue.  Queue characteristics
 * are defined by the endpoint's descriptor.  This cookie is called a "pipe",
 * an unsigned int encoded as:
 *
 *  - direction:    bit 7       (0 = Host-to-Device [Out],
 *                   1 = Device-to-Host [In] ...
 *                  like endpoint bEndpointAddress)
 *  - device address:   bits 8-14       ... bit positions known to uhci-hcd
 *  - endpoint:     bits 15-18      ... bit positions known to uhci-hcd
 *  - pipe type:    bits 30-31  (00 = isochronous, 01 = interrupt,
 *                   10 = control, 11 = bulk)
 *
 * Given the device address and endpoint descriptor, pipes are redundant.
 */

/* NOTE:  these are not the standard USB_ENDPOINT_XFER_* values!! */
/* (yet ... they're the values used by usbfs) */
#define PIPE_ISOCHRONOUS        0
#define PIPE_INTERRUPT          1
#define PIPE_CONTROL            2
#define PIPE_BULK           3

#define usb_pipein(pipe)    ((pipe) & USB_DIR_IN)
#define usb_pipeout(pipe)   (!usb_pipein(pipe))

#define usb_pipedevice(pipe)    (((pipe) >> 8) & 0x7f)
#define usb_pipeendpoint(pipe)  (((pipe) >> 15) & 0xf)

#define usb_pipetype(pipe)  (((pipe) >> 30) & 3)
#define usb_pipeisoc(pipe)  (usb_pipetype((pipe)) == PIPE_ISOCHRONOUS)
#define usb_pipeint(pipe)   (usb_pipetype((pipe)) == PIPE_INTERRUPT)
#define usb_pipecontrol(pipe)   (usb_pipetype((pipe)) == PIPE_CONTROL)
#define usb_pipebulk(pipe)  (usb_pipetype((pipe)) == PIPE_BULK)

static inline unsigned int __create_pipe(struct usb_device *dev,
        unsigned int endpoint)
{
    return (dev->devnum << 8) | (endpoint << 15);
}

/* Create various pipes... */
#define usb_sndctrlpipe(dev, endpoint)  \
    ((PIPE_CONTROL << 30) | __create_pipe(dev, endpoint))
#define usb_rcvctrlpipe(dev, endpoint)  \
    ((PIPE_CONTROL << 30) | __create_pipe(dev, endpoint) | USB_DIR_IN)
#define usb_sndisocpipe(dev, endpoint)  \
    ((PIPE_ISOCHRONOUS << 30) | __create_pipe(dev, endpoint))
#define usb_rcvisocpipe(dev, endpoint)  \
    ((PIPE_ISOCHRONOUS << 30) | __create_pipe(dev, endpoint) | USB_DIR_IN)
#define usb_sndbulkpipe(dev, endpoint)  \
    ((PIPE_BULK << 30) | __create_pipe(dev, endpoint))
#define usb_rcvbulkpipe(dev, endpoint)  \
    ((PIPE_BULK << 30) | __create_pipe(dev, endpoint) | USB_DIR_IN)
#define usb_sndintpipe(dev, endpoint)   \
    ((PIPE_INTERRUPT << 30) | __create_pipe(dev, endpoint))
#define usb_rcvintpipe(dev, endpoint)   \
    ((PIPE_INTERRUPT << 30) | __create_pipe(dev, endpoint) | USB_DIR_IN)

static inline struct usb_host_endpoint *
usb_pipe_endpoint(struct usb_device *dev, unsigned int pipe)
{
    struct usb_host_endpoint **eps;
    eps = usb_pipein(pipe) ? dev->ep_in : dev->ep_out;
    return eps[usb_pipeendpoint(pipe)];
}

/*-------------------------------------------------------------------------*/

static inline __u16
usb_maxpacket(struct usb_device *udev, int pipe, int is_out)
{
    struct usb_host_endpoint    *ep;
    unsigned            epnum = usb_pipeendpoint(pipe);

    if (is_out) {
        WARN_ON(usb_pipein(pipe));
        ep = udev->ep_out[epnum];
    } else {
        WARN_ON(usb_pipeout(pipe));
        ep = udev->ep_in[epnum];
    }
    if (!ep)
        return 0;

    /* NOTE:  only 0x07ff bits are for packet size... */
    return usb_endpoint_maxp(&ep->desc);
}

/* ----------------------------------------------------------------------- */

/* translate USB error codes to codes user space understands */
static inline int usb_translate_errors(int error_code)
{
    switch (error_code) {
    case 0:
    case -ENOMEM:
    case -ENODEV:
    case -EOPNOTSUPP:
        return error_code;
    default:
        return -EIO;
    }
}

/* Events from the usb core */
#define USB_DEVICE_ADD      0x0001
#define USB_DEVICE_REMOVE   0x0002
#define USB_BUS_ADD     0x0003
#define USB_BUS_REMOVE      0x0004
extern void usb_register_notify(struct notifier_block *nb);
extern void usb_unregister_notify(struct notifier_block *nb);

/* debugfs stuff */
extern struct dentry *usb_debug_root;

#endif  /* __KERNEL__ */

#endif